On-board equipment and determination method

Abstract

To provide a new technology that enables position detection without using GNSS or ground transponders. [Solution] The on-board device 1 includes a magnetic sensor unit 10 having a plurality of magnetic sensor elements arranged in a predetermined positional relationship to detect a magnetic field generated by the magnetism of the magnetic material constituting the track, a detection unit 353 that detects the magnetic field distribution based on the detected values ​​of each magnetic sensor element, and a determination unit 355 that determines the passage of a predetermined set position when a combination of similarity of magnetic field distributions detected by the detection unit 353 for each of a plurality of reference magnetic field distributions satisfies a predetermined condition.

Description

Technical Field

[0001] The present invention relates to an on-vehicle device mounted on a vehicle traveling on a track and the like.

Background Art

[0002] Conventionally, there are known techniques for detecting the position of a vehicle by detecting a ground unit installed on the ground or by satellite positioning using GNSS (Global Navigation Satellite System). There is also known a technique for detecting the vehicle position by installing a magnetic marker (permanent magnet) on the ground and detecting it on the vehicle side (see Patent Document 1).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, in the method of detecting the vehicle position using the positioning result of GNSS, there is a problem of positioning error because the positioning position varies. In the case of the method of detecting a ground unit or a magnetic marker, installation of a ground unit or the like is required at each detection location, which leads to an increase in installation costs and the like.

[0005] The problem to be solved by the present invention is to provide a new technology capable of detecting the position without using GNSS or a ground unit.

Means for Solving the Problems

[0006] A first invention for solving the above problems is an on-vehicle device mounted on a vehicle traveling on a track, A magnetic sensor unit having a plurality of magnetic sensor elements arranged in a predetermined positional relationship to detect a magnetic field generated by the magnetism of the magnetic material constituting the orbit, A detection unit for detecting the magnetic field distribution based on the detected values ​​of each of the aforementioned magnetic sensor elements, A determination unit determines that a predetermined set position has been passed when a combination of similarity between the magnetic field distributions detected by the detection unit for each of multiple reference magnetic field distributions satisfies a predetermined condition. This is an on-board device equipped with [a specific feature / feature].

[0007] Furthermore, other inventions include: A method for determining the passing position of a vehicle equipped with a magnetic sensor unit having a plurality of magnetic sensor elements arranged in a predetermined positional relationship to detect a magnetic field generated by the magnetism of magnetic materials constituting the track, To detect the magnetic field distribution based on the detected values ​​of each of the aforementioned magnetic sensor elements, When the combination of similarity between the magnetic field distributions detected by the detection unit for each of the multiple reference magnetic field distributions satisfies predetermined conditions, it is determined that the device has passed a predetermined set position. This is a determination method that includes [something].

[0008] According to the first invention, an on-board device mounted on a vehicle can determine the passage of a predetermined set position. Specifically, a magnetic sensor unit is installed on the vehicle to detect the magnetic field distribution (detected magnetic field distribution) generated by the magnetism of the magnetic materials constituting the track. When a combination of similarity between the detected magnetic field distribution and each of several reference magnetic field distributions satisfies a predetermined condition, it can be determined that the vehicle has passed the set position. This makes it possible to detect the position without using GNSS or ground coils.

[0009] The second invention relates to the above invention, Multiple positions are defined as the aforementioned setting positions, each having a different magnetic field distribution detected by the detection unit. The determination unit identifies the set position and determines whether it has passed by determining whether the conditions related to the combination of similarity defined for each set position are met. It is an on-board device.

[0010] According to the second invention, conditions relating to the combination of similarity with each reference magnetic field distribution are defined for each set position. By determining the conditions for each set position, it becomes possible to identify the set position and determine passage through it.

[0011] The third invention is, in the above invention, As the aforementioned setting positions, a plurality of positions with different magnetic field distributions detected by the detection unit are defined, and the order in which these plurality of setting positions arrive as the vehicle travels is associated. The determination unit determines whether the next sequential setting position has been passed by determining whether the conditions corresponding to the next sequential setting position that follows the setting position that was determined to have been passed in the most recent past are met among the conditions related to the combination of similarity determined for each setting position. It is an on-board device.

[0012] According to the third invention, by selecting the next setting position from among a plurality of setting positions in the order in which they arrive as the vehicle travels, and determining the conditions corresponding to the next setting position, it becomes possible to determine the sequential passage of the setting positions.

[0013] The fourth invention is, in the above invention, A reference similarity is defined for each of the reference magnetic field distributions at the aforementioned setting position. The determination unit calculates the calculation similarity of the magnetic field distribution detected by the detection unit to each of the reference magnetic field distributions, and determines the exact passing timing of the set position based on the comparison result obtained by comparing the calculated similarity with the corresponding reference similarity. It is an on-board device.

[0014] According to the fourth invention, the exact timing of passing through a set position can be determined by comparing the reference similarity for each reference magnetic field distribution with the calculated similarity of the magnetic field distribution detected by the detection unit.

[0015] The fifth invention is, in the above invention, The magnetic sensor unit has at least a plurality of magnetic sensor elements arranged in the left - right direction of the vehicle. It is an on - vehicle device.

[0016] According to the fifth invention, the plurality of magnetic sensor elements included in the magnetic sensor unit are arranged at least in the left - right direction orthogonal to the front - rear direction which is the traveling direction of the vehicle.

[0017] The sixth invention is, in the above invention, The magnetic sensor unit has at least a plurality of magnetic sensors arranged in a planar shape along the front - rear, left - right directions of the vehicle. It is an on - vehicle device.

[0018] According to the sixth invention, the plurality of magnetic sensor elements included in the magnetic sensor unit are arranged at least in a planar shape along the front - rear, left - right directions of the vehicle.

[0019] The seventh invention is, in the above invention, The magnetic body is a rail. It is an on - vehicle device.

[0020] According to the seventh invention, it becomes possible to determine the passage of a set position by utilizing the detection of the magnetic field generated by the magnetism of the rail.

Brief Description of the Drawings

[0021] [Figure 1] A diagram showing an application example of an on - vehicle device. [Figure 2] A diagram showing a configuration example of a magnetic sensor unit. [Figure 3] A diagram showing an example of calculating a calculated correlation coefficient. [Figure 4] A diagram for explaining the outline of combination determination. [Figure 5] A diagram for explaining the determination of just - passing timing. [Figure 6] A block diagram showing a functional configuration example of an on - vehicle control device. [Figure 7] This diagram shows an example of the data structure for the set position data. [Figure 8] A flowchart illustrating the processing flow performed by the on-board control system. [Modes for carrying out the invention]

[0022] Preferred embodiments of the present invention will be described below with reference to the drawings. However, the present invention is not limited to the embodiments described below, nor are the applicable forms of the present invention limited to the embodiments described below. Furthermore, the same parts are denoted by the same reference numerals in the drawings.

[0023] Figure 1 is a schematic diagram illustrating an example of the application of the on-board device in this embodiment. As shown in Figure 1, the on-board device 1 is mounted on a railway vehicle 3 that runs on rails 5 and comprises a magnetic sensor unit 10 and an on-board control device 30.

[0024] The magnetic sensor unit 10 is a detection unit for detecting the magnetic field generated by the magnetism of the rail 5, and is installed in a position where it can detect the magnetism in the magnetic field generated by the rail 5. For example, the magnetic sensor unit 10 is installed on the bottom or bogie of the railway vehicle 3 so as to face the rail 5.

[0025] Figure 2 is a diagram showing an example configuration of the magnetic sensor unit 10, and is a schematic plan view of the magnetic sensor unit 10 as seen from above. As shown in Figure 2, the magnetic sensor unit 10 has a plurality of magnetic sensor elements 12 arranged in a planar manner facing the rail 5. In the example in Figure 2, the magnetic sensor unit 10 is shown having a total of 16 magnetic sensor elements 12 arranged in a planar manner, with 4 rows in the left-right direction and 4 rows in the front-rear direction (direction of travel) of the railway vehicle 3. The spacing between adjacent magnetic sensor elements 12 is such that they do not overlap, and it is preferable that the distance between the centers of the magnetic sensor elements 12 in both the left-right and front-rear directions is within 150 mm.

[0026] The arrangement of the magnetic sensor elements 12 in the magnetic sensor unit 10 is not limited to the example arrangement of 16 elements in total, consisting of 4 rows in the left-right direction and 4 rows in the front-back direction (travel direction), but can be set as appropriate. Furthermore, the magnetic sensor unit 10 may be configured with multiple magnetic sensor elements 12 arranged only in the left-right direction.

[0027] The magnetic sensor element 12 is an element that detects the magnetism in the magnetic field generated around the rail 5 by the magnetism of the rail 5, and outputs a current or voltage as a detected value corresponding to the magnitude and direction of the detected magnetism. In this embodiment, the magnetic sensor element 12 is a three-axis sensor having three detection axes (X axis, Y axis, and Z axis), with the X axis aligned with the front-rear direction of the railway vehicle 3, the Y axis aligned with the left-right direction of the railway vehicle 3, and the Z axis aligned with the up-down direction of the railway vehicle 3. For example, the magnetic sensor element 12 is a Hall element, a magnetoresistive element (MR element), a magnetoimpedance element (MI element), a flux-gate sensor, etc. The detected value of the magnetic sensor element 12 is output to the on-board control device 30.

[0028] The on-board control device 30 uses the detection of magnetism by the magnetic sensor unit 10 to determine when the railway vehicle 3 has passed set positions P1, P2, ..., ... on the rails 5. In this embodiment, set positions P1, P2, ..., ... are predetermined within the target line section on which the railway vehicle 3 travels, and each set position P1, P2, ..., ... is associated with the order in which it arrives as the railway vehicle 3 travels. In the example in Figure 1, the order of arrival is associated with set position P1 as the first, set position P2 as the second, and so on.

[0029] Here, the rail 5 is a ferromagnetic material and is magnetized during manufacturing and transportation due to the influence of the external environment at the time, but the form of magnetization is not uniform. Therefore, the magnetism at various points on the laid rail 5 is not constant, and the magnetic field generated at a given location (generated magnetic field) differs depending on the position on the rail 5. In other words, the magnetic field distribution detected by the magnetic sensor unit 10 when the railway vehicle 3 passes over each set position P1, P2, ..., ... is different. The on-board control device 30 uses this to determine when the vehicle has passed over the set positions P1, P2, ..., ....

[0030] [detail] The on-board control device 30 detects the magnetic field distribution based on the detection values ​​of each magnetic sensor element 12 while the railway vehicle 3 is in motion. The on-board control device 30 then calculates the similarity of the detected magnetic field distribution to each of several reference magnetic field distributions, and determines that the vehicle has passed a set position if the combination of calculated similarities satisfies predetermined conditions.

[0031] Furthermore, while the railway vehicle 3 is in motion, the on-board control device 30 uses the detection of magnetism by the magnetic sensor unit 10 to separately calculate the travel position (kilometers) of the railway vehicle 3. Then, if the on-board control device 30 determines that the vehicle has passed a set position, it corrects the travel position using the kilometers of that set position.

[0032] 1. Regarding the reference magnetic field distribution In this embodiment, several different types of reference magnetic field distributions are predetermined. The number of reference magnetic field distributions is not particularly limited, but five types (reference magnetic field distributions A to E; see Figure 3) will be described below.

[0033] The reference magnetic field distribution can be set as appropriate. For example, it can be set based on the magnetic field distribution at various points along the rail 5. The magnetic field distribution can be obtained by detecting the magnetic field distribution at various points using the magnetic sensor unit 10 while the railway vehicle 3 is running. For example, the magnetic field distribution at locations with a large magnetic field within the target line section or at each set position P1, P2, ..., ... can be obtained and set as the reference magnetic field distribution.

[0034] 2. Regarding the determination of similarity combinations In this embodiment, for each designated location, a correlation coefficient (reference correlation coefficient) between the generated magnetic field distribution at that location and the reference magnetic field distribution is predetermined as the reference similarity. For example, the generated magnetic field distribution at each designated location is acquired, and the correlation coefficient between the acquired generated magnetic field distribution and the reference magnetic field distribution is calculated. Then, the obtained correlation coefficients are set as the reference correlation coefficient for each reference magnetic field distribution for each designated location.

[0035] Meanwhile, while the railway vehicle 3 is in motion, the on-board control device 30 calculates a correlation coefficient between the detected magnetic field distribution, which is detected at any given time, and each of the reference magnetic field distributions, and obtains this as a calculated similarity. The on-board control device 30 then compares the correlation coefficient (calculated correlation coefficient; calculated similarity) calculated for each of the reference magnetic field distributions with the reference correlation coefficient for each set position P1, P2, ..., ... to perform a combination determination.

[0036] Let me explain in more detail. Figure 3 is a graph showing the calculated correlation coefficients for each of the reference magnetic field distributions A to E while the railway vehicle 3 was in motion, with the elapsed time from the start of travel on the horizontal axis and the correlation coefficient value on the vertical axis. The elapsed time on the horizontal axis can be said to represent the travel position. The correlation coefficient is calculated as a value between "-1" and "1", and a larger absolute value (closer to "1") indicates a stronger correlation (= higher similarity), while a smaller absolute value indicates a weaker correlation (= lower similarity).

[0037] When deciding where to set the location on rail 5, it is advisable to consider the correlation coefficient with reference magnetic field distributions A to E. Specifically, the setting location should be a place that has a strong correlation with at least one of the reference magnetic field distributions A to E. It is even more preferable to select a location where the absolute value of the correlation coefficient with at least one reference magnetic field distribution is "0.8 or higher". For example, focusing on the location (kilometer mileage) on rail 5 corresponding to time ta in Figure 3, the absolute value of the correlation coefficient with the two reference magnetic field distributions C and E exceeds "0.8", making it a suitable setting location.

[0038] Let's assume that the position of the railway vehicle 3 is, for example, time ta, indicated by the dashed line in Figure 3. The onboard control device 30 calculates correlation coefficients between the detected magnetic field distribution detected at time ta and each of the reference magnetic field distributions A to E. These are the calculated correlation coefficients C1 to C5 in Figure 3. The onboard control device 30 compares these calculated correlation coefficients C1 to C5 with each of the reference correlation coefficients related to the set position P1 to determine if they are a compatible combination. If they are not compatible, it is determined that the vehicle is not at the set position P1; if they are compatible, it is determined that the vehicle is at the set position P1. This process is performed for each set position P1, P2, ..., ... to determine whether the vehicle has passed the set position.

[0039] Figure 4 is a diagram illustrating the overview of the combination determination. As described above, in this embodiment, for each predetermined position, the correlation coefficient between the generated magnetic field distribution and the reference magnetic field distribution at that position is defined as the reference correlation coefficient (reference correlation coefficient data 375 in Figure 4(a)). In the combination determination, the on-board control device 30 uses the combination of reference correlation coefficients for each predetermined position to determine the conditions related to that combination. For example, focusing on the predetermined position P1, the passage through the predetermined position P1 is determined by whether or not the conditions corresponding to the predetermined position P1 (specifically, the conditions related to the combination of reference correlation coefficients D11 defined for the predetermined position P1) are met. For the predetermined position P2, the passage through the predetermined position P2 is determined by whether or not the conditions corresponding to the predetermined position P2 (specifically, the conditions related to the combination of reference correlation coefficients D13 defined for the predetermined position P2) are met.

[0040] For example, Figure 4(b) shows a determination example focusing on the set position P1. In this example, the on-board control device 30 uses the combination of reference correlation coefficients D11 related to the set position P1 to determine whether the combination of calculated correlation coefficients D2 calculated for the detected magnetic field distribution satisfies predetermined conditions.

[0041] The conditions for determination here can be set, for example, as "all calculated correlation coefficients are within a tolerance range with respect to the corresponding reference correlation coefficient." The tolerance range can be set as appropriate, but the narrower the range, the more accurately the set position can be determined. For example, Figure 4(b) shows an example of determination when the tolerance range is "within ±0.1 of the reference correlation coefficient." The on-board control device 30 compares the combination of reference correlation coefficients D11 related to the set position P1 with the combination of calculated correlation coefficients D2, and determines that the railway vehicle 3 has passed the set position P1 if all calculated correlation coefficients are within ±0.1 of the corresponding reference correlation coefficient.

[0042] More specifically, prior to determining the combination, the on-board control device 30 selects the next arriving setting position according to the arrival order associated with each setting position. Then, the on-board control device 30 monitors whether the conditions corresponding to the next setting position are met, and determines that the next setting position has been passed when it determines that the conditions are met. For example, it first selects the first setting position P1 as the next setting position and determines that the conditions corresponding to setting position P1 are met. If the on-board control device 30 determines that the conditions are met and that the next setting position has been passed, and has completed the determination of the just-pass timing described later, it selects setting position P2, which is the second in the arrival order, as the new next setting position and proceeds to determine the setting position P2.

[0043] In the example of time point ta in Figure 3, the tolerance ranges for the reference correlation coefficients related to the next sequential setting position for the calculated correlation coefficients C1 to C5 are shown with hatching. At time point ta, the calculated correlation coefficients C1 to C5 are each within the tolerance range of the reference correlation coefficient for the corresponding reference magnetic field distribution, and since the condition is met, it is determined that the next sequential setting position has been passed.

[0044] 3. Determining the exact timing of passing When the onboard control device 30 determines that the railway vehicle 3 has passed the next designated position in the manner described above, it determines the exact timing of passing the designated position. Figure 5 is a diagram illustrating the determination of the exact timing of passing. In Figure 5, the horizontal axis represents the elapsed time indicating the change in the travel position, and the vertical axis represents the sum S of equation (1) described later, showing an example of the change in the sum S in response to the change in the travel position.

[0045] For example, the on-board control device 30 continues to determine the conditions corresponding to the next set position even after determining that the vehicle has passed the next set position in order to determine the exact timing of passing. The on-board control device 30 then continuously calculates the sum S according to equation (1) until any of the calculated correlation coefficients falls outside the tolerance range of the corresponding reference correlation coefficient and the conditions are no longer met. Specifically, the difference between the calculated correlation coefficient Cn and the reference correlation coefficient Rn is calculated for each reference magnetic field distribution, and the sum of the absolute values ​​of the obtained differences is calculated. In equation (1), n ​​(n=1~5) represents each of the five types of reference magnetic field distributions. S = Σ|Cn - Rn|···(1)

[0046] If the value is no longer within the tolerance range, i.e., the condition is no longer met, the on-board control device 30 identifies the time td at which the sum value S is minimized within a predetermined period after the condition was met (between time tb and time tc in the example of Figure 5), and determines that time td to be the exact timing for passing the next set position. In that case, the on-board control device 30 corrects the running position of the railway vehicle 3 at the exact passing timing as the kilometer mileage of the next set position.

[0047] Furthermore, the configuration is not limited to identifying the point in time when the sum value S is minimized; it may also be configured so that the point in time when the sum value S satisfies a predetermined threshold condition is considered the exact timing for passing the next position. The threshold condition can be set, for example, as "the sum value S is less than or equal to a predetermined value Ta." In the example in Figure 5, the point in time te when the sum value becomes less than or equal to the predetermined value Ta after the point in time tb when the condition is met may be determined as the exact timing for passing the next position.

[0048] 4. Calculation of the driving position As described above, the rail 5 is a ferromagnetic material and is magnetized during manufacturing and transportation due to the influence of the external environment at the time, but the form of magnetization is not uniform. Therefore, the time-series data of the detected value of the magnetic sensor element 12 in the magnetic sensor unit 10 will be a waveform in which the magnetic flux density changes according to time (more precisely, the position of travel).

[0049] Here, focusing on a combination of two magnetic sensor elements 12 (sensor pair) of the magnetic sensor elements 12 of the magnetic sensor unit 10 that are aligned along the direction of travel of the railway vehicle 3, the waveforms of the magnetic flux density, which are the time-series data of the detected values, are approximately identical, although there is a time difference in the detection time. Then, from the time difference (time difference) Δt between these two waveforms and the spacing d between each magnetic sensor element 12 along the direction of travel, the travel speed v of the railway vehicle 3 can be calculated using equation (2). v = d / Δt ... (2)

[0050] Therefore, the on-board control device 30 calculates the running speed of the railway vehicle 3 at predetermined time intervals. The on-board control device 30 then calculates the distance traveled by the railway vehicle 3 by integrating the obtained running speed with respect to time, and calculates the running position (kilometers) of the railway vehicle 3 by accumulating the distance traveled from a given starting position.

[0051] The two magnetic sensor elements 12 used to calculate the travel speed may be selected as appropriate. For example, the on-board control device 30 selects the combination (sensor set) of magnetic sensor elements 12 that are furthest apart along the direction of travel. In the example in Figure 2, the magnetic sensor unit 10 has four rows of magnetic sensor elements 12 arranged in the front-rear direction of the railway vehicle 3, so four combinations of the magnetic sensor elements 12 in the first row (front row) and the magnetic sensor elements 12 in the fourth row (back row) are selected: (A,M), (B,N), (C,O), (D,P).

[0052] The on-board control device 30 then calculates the running speed v for each selected combination (sensor set) according to equation (2), based on the time difference Δt of the waveform of the magnetic flux density, which is the time-series data of the detected values ​​of each of the two magnetic sensor elements 12 related to the sensor set, and the spacing d between the two magnetic sensor elements 12 related to the sensor set along the direction of travel. Finally, it performs a predetermined statistical calculation (for example, calculation of the average value) on the running speed v calculated for each sensor set to determine the running speed of the railway vehicle 3.

[0053] [Functional Configuration] Figure 6 is a block diagram showing an example of the functional configuration of the on-board control device 30. As shown in Figure 6, the on-board control device 30 comprises an operation unit 310, a display unit 320, a communication unit 330, a processing unit 350, and a storage unit 370, and is configured as a type of computer system.

[0054] The operation unit 310 is implemented by an input device such as a button switch or a touch panel, and outputs an operation signal to the processing unit 350 in accordance with the operation input. The display unit 320 is implemented by a display device such as an LCD (Liquid Crystal Display) or a touch panel, and displays various information in accordance with the display signal from the processing unit 350. The communication unit 330 is implemented by a wired or wireless communication device, and communicates with a predetermined external device.

[0055] The processing unit 350 is implemented, for example, by an arithmetic circuit such as a CPU (Central Processing Unit) or a control board including said arithmetic circuit, and controls the operation of the on-board device 1 by performing various arithmetic processes based on programs and data stored in the storage unit 370. In this embodiment, the processing unit 350 includes a driving position calculation unit 351, a detection unit 353, a determination unit 355, and a driving position correction unit 357. Each of these functional units may be an arithmetic processing block implemented as software by executing a program, or it may be a circuit block implemented by a signal processing circuit. In this embodiment, the processing unit 350 is described as an arithmetic processing block implemented as software by executing a predetermined program.

[0056] The position calculation unit 351 calculates the distance traveled by the railway vehicle 3 using the magnetic detection by the magnetic sensor unit 10, and calculates the position of the railway vehicle 3 in real time by accumulating the distance traveled from a given starting position. The position of the railway vehicle 3 is stored in the storage unit 370 as the current position 379. The method for calculating the position is not particularly limited. For example, the position (distance traveled) of the railway vehicle 3 may be calculated in real time based on the detection signal of a rotation detector such as a pulse generator or speed generator that detects the rotation of the wheels or axles.

[0057] While the railway vehicle 3 is in motion, the detection unit 353 continuously detects the magnetic field distribution of the rail 5 located opposite the magnetic sensor unit 10, based on the detection values ​​of each of the magnetic sensor elements 12 of the magnetic sensor unit 10.

[0058] The determination unit 355 calculates a correlation coefficient (calculated correlation coefficient) as the similarity of the detected magnetic field distribution to each of a plurality of reference magnetic field distributions, and determines whether the combination of calculated correlation coefficients for each reference magnetic field distribution obtained satisfies predetermined conditions (combination determination). In this embodiment, the determination unit 355 selects the next sequential setting position that will arrive next according to the arrival order associated with each setting position. The determination unit 355 then compares the calculated correlation coefficient for each reference magnetic field distribution with the reference correlation coefficient related to the next sequential setting position, and determines that the next sequential setting position has been passed if the combination of calculated correlation coefficients satisfies the conditions corresponding to the next sequential setting position. In that case, the determination unit 355 also determines the exact timing of the railway vehicle 3 passing the next sequential setting position.

[0059] The travel position correction unit 357 corrects the travel position calculated by the travel position calculation unit 351 using the kilometer distance of the set position whose passage has been determined by the determination unit 355. In this embodiment, when the passage of the set position selected as the next sequential set position is determined and the exact timing of its passage is determined, the travel position at the exact timing of its passage is used as the kilometer distance of the set position to correct the travel position.

[0060] The memory unit 370 is implemented using a storage medium such as an IC memory or a hard disk. The memory unit 370 pre-stores programs for operating the on-board device 1 and realizing the various functions of the on-board device 1, as well as data used during the execution of such programs, or temporarily stores them each time processing is performed. In this embodiment, the memory unit 370 stores set position data 371, reference magnetic field distribution data 373, reference correlation coefficient data 375, detection data 377, and the current driving position 379.

[0061] The set position data 371 is data of the set positions (detection locations; for example, set positions P1, P2, ..., ...) on the rail 5 for determining passage. Figure 7 shows an example of the data structure of the set position data 371. As shown in Figure 7, for each set position, the set position data 371 is set with an identification ID (set position ID) for that set position and the kilometer distance to that set position, corresponding to the order in which it arrives.

[0062] The reference magnetic field distribution data 373 stores data for multiple types of reference magnetic field distributions (five types of reference magnetic field distributions A to E in the example of Figure 3). The reference correlation coefficient data 375 stores the correlation coefficient between the generated magnetic field distribution and the reference magnetic field distribution at each set location as the reference correlation coefficient (see Figure 4(a)).

[0063] The detection data 377 is generated each time the magnetic sensor unit 10 detects something, and stores the detected value of each magnetic sensor element 12, the calculated correlation coefficient for each reference magnetic field distribution, and so on. The detection data 377 also stores the data of the current driving position 379 at the time of detection. This is used as reference information for the driving position at the time the vehicle passed a set position when there is a time difference between the timing of correcting the driving position calculated on the vehicle and the timing of passing a set position.

[0064] [Process flow] Figure 8 is a flowchart showing the processing flow performed by the on-vehicle control device 30. As shown in Figure 8, first, the driving position calculation unit 351 starts calculating the driving position (step S1).

[0065] Furthermore, the determination unit 355 selects the setting position associated with the first arrival order as the next setting position (step S3). Then, the detection unit 353 starts detecting the magnetic field distribution using the magnetic sensor unit 10 (step S5).

[0066] The determination unit 355 then calculates the correlation coefficient between the detected magnetic field distribution detected by the detection unit 353 at any given time and the reference magnetic field distribution (step S7). The determination unit 355 then compares the calculated correlation coefficient for each reference magnetic field distribution calculated in step S7 with the reference correlation coefficient defined for the next sequential setting position and determines whether the combination of calculated correlation coefficients satisfies the conditions corresponding to the next sequential setting position (conditions based on the reference correlation coefficient related to the next sequential setting position) (step S9). If the conditions are met (step S11: YES), the determination unit 355 determines that the railway vehicle 3 has passed the next sequential setting position (step S13).

[0067] Subsequently, the determination unit 355 identifies the point in time when the sum S of equation (1) is minimized within the period that satisfies the conditions corresponding to the next sequence setting position, and determines that point in time as the exact timing of passing the next sequence setting position (step S15).

[0068] Then, once the exact passing timing has been determined, the running position correction unit 357 updates the running position of the railway vehicle 3 at the exact passing timing determined in step S15 with the kilometer mileage of the next set position, and corrects the running position (step S17).

[0069] Then, the determination unit 355 selects the next setting position in the arrival order as the new next setting position (step S19), and returns to step S7 to repeat the process described above.

[0070] Furthermore, if the determination unit 355 determines in step S9 that the conditions are not met (step S11: NO), it determines whether the running position of the railway vehicle 3, calculated by the running position calculation unit 351, has reached the kilometer mileage of the next set position. If the running position has not reached the next set position (step S21: NO), it returns to step S7 and repeats the process described above. On the other hand, if the running position has reached the kilometer mileage of the next set position (step S21: YES), it determines that it is not possible to properly determine that the vehicle has passed the set position, and activates the emergency brake to stop the railway vehicle 3 (step S23).

[0071] As described above, according to this embodiment, the on-board device 1 mounted on the railway vehicle 3 can determine the passage of a predetermined set position. In other words, the magnetic sensor unit 10 detects the magnetic field distribution generated by the magnetism of the rail 5. When the combination of similarity between the detected magnetic field distribution and each of the multiple reference magnetic field distributions satisfies predetermined conditions, it is possible to determine that the vehicle has passed the set position. This makes it possible to detect the position without using GNSS or ground beacons.

[0072] It should be noted that the applicable embodiments of the present invention are not limited to those described above, and components can be added, omitted, or modified as appropriate.

[0073] [Example 1] For example, in the above embodiment, five types of reference magnetic field distributions A to E are used to determine passage through a set position. Alternatively, the target railway line may be divided into multiple sections, and the reference magnetic field distribution applied to each section may be changed. For example, the target railway line may be divided into multiple sections such that each section contains at least one set position. Multiple types of reference magnetic field distributions may be set for each divided section. In addition, for each set position, the correlation coefficient between the magnetic field distribution generated at that set position and the reference magnetic field distribution of the section to which that set position belongs may be set as the reference correlation coefficient for that set position. While the railway vehicle 3 is in motion, the reference magnetic field distribution of the section to which the vehicle is traveling belongs is applied to calculate the correlation coefficient, and a combination determination is made.

[0074] [Differentiation 2] Furthermore, although the above embodiment used rail 5 as an example of a magnetic material constituting the track, it is not limited to rail 5. For example, the magnetic field generated by the magnetism of a magnetic material such as a PC sleeper (a sleeper made of prestressed concrete) or reinforcing steel contained in a slab track may be detected to determine when the train has passed a set position. [Explanation of Symbols]

[0075] 1...Onboard device 10…Magnetic sensor section 12…Magnetic sensor element 30... On-board control device 350… Processing Unit 351...Travel position calculation unit 353...Detection unit 355…Judgment section 357...Travel position correction unit 370...Storage section 371...Setting position data 373...Reference magnetic field distribution data 375…Reference correlation coefficient data 377…Detection data 379...Current location 3…Railway vehicles 5... Rails

Claims

1. An on-board device mounted on a vehicle that travels on a track, A magnetic sensor unit having a plurality of magnetic sensor elements arranged in a predetermined positional relationship to detect a magnetic field generated by the magnetism of the magnetic material constituting the orbit, A detection unit for detecting the magnetic field distribution based on the detected values ​​of each of the aforementioned magnetic sensor elements, A determination unit determines that a predetermined set position has been passed when a combination of similarity between the magnetic field distributions detected by the detection unit for each of multiple reference magnetic field distributions satisfies a predetermined condition. An on-board device equipped with the following features.

2. Multiple positions are defined as the aforementioned setting positions, each having a different magnetic field distribution detected by the detection unit. The determination unit identifies the set position and determines whether it has passed by determining whether the conditions related to the combination of similarity defined for each set position are met. The on-board device according to claim 1.

3. As the aforementioned setting positions, a plurality of positions with different magnetic field distributions detected by the detection unit are defined, and the order in which these plurality of setting positions arrive as the vehicle travels is associated. The determination unit determines whether the next sequential setting position has been passed by determining whether the conditions corresponding to the next sequential setting position that follows the setting position that was determined to have been passed in the most recent past are met among the conditions related to the combination of similarity determined for each setting position. The on-board device according to claim 1.

4. A reference similarity is defined for each of the reference magnetic field distributions at the aforementioned setting position. The determination unit calculates the calculation similarity of the magnetic field distribution detected by the detection unit to each of the reference magnetic field distributions, and determines the exact passing timing of the set position based on the comparison result obtained by comparing the calculated similarity with the corresponding reference similarity. The on-board device according to claim 1.

5. The magnetic sensor unit has at least a plurality of magnetic sensor elements arranged in the left-right direction of the vehicle. The on-board device according to claim 1.

6. The magnetic sensor unit has at least a plurality of magnetic sensors arranged in a planar shape along the front, rear, left, and right directions of the vehicle. The on-board device according to claim 1.

7. The magnetic material is a rail. The on-board device according to any one of claims 1 to 6.

8. A method for determining the passing position of a vehicle equipped with a magnetic sensor unit having a plurality of magnetic sensor elements arranged in a predetermined positional relationship to detect a magnetic field generated by the magnetism of magnetic materials constituting the track, To detect the magnetic field distribution based on the detected values ​​of each of the aforementioned magnetic sensor elements, When the combination of similarity between the magnetic field distributions detected by the detection unit for each of the multiple reference magnetic field distributions satisfies predetermined conditions, it is determined that the device has passed a predetermined set position. A determination method that includes this.

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